This is all fine and dandy. Simply do not forget that these free digital coupon codes which were given to you by Amazon for free once they are discovered that you are giving them away for the wrong purpose or selling them for the wrong purpose , every single code that this person has will be revoked this could be 6 months down the road. This could be a year down the road, this happens a lot with the Google AdWords people that are given hundreds and hundreds of codes they sell them.
I have been using credit coupon codes for years, sometimes from events i have attended myself, sometimes given to me by friends that attended these events, sometimes buying them from places like bitcointalk if i couldn't attend & didn't have any friends that wanted to give me their coupon code.
And i never had a single problem.
Look, amazon is in the business of making money, they want people to use these coupon codes so they get addicted and create successfully application ontop of AWS so they lock themselves in. (a completely different business model than Google AdWords) Its like how drug dealers give you the first hit of whatever narcotic they’re selling to get you addicted. Then they start charging you money when you’re addicted and desperate.
The people that buy these coupon codes here generally either have been legit longterm AWS customers spending big $$$$ over the years (coupon usage is a rounding error compared to real profit/revenue generated by their AWS accounts), or they are new customers, setting up anonymous accounts (setup with a proxy & vcc etc). Either way, the fallout of coupon sharing being detected should be limited, since Amazon doesn't want to piss of the first (since they just "got the coupon code from my friend, which is sitting right next to me") and can't track the second.
I highly doubt that coupon code sharing will be detected in the first place though, since the coupon codes were given to people with different names, from different countries, different email addresses, different ip addresses etc. There isn't a single thing shared across the coupons, which makes a doomsday scenario highly unlikely.